1. Field of the Invention
This invention relates to apparatus for improving visual feedback by illuminating a field such as a reading area, hobby area or any other field such as a surgical site during a medical procedure, and more particularly, to a finger-mounted light which, in the preferred embodiment, includes at least one light-emitting diode capable of emitting light of selected color.
2. General Background
This invention can be used for many different applications where a beam of light needs to be positioned near a work place. Some examples are the assembly of small components by hobbyists, reaching into dark passages by mechanics, assembly or inspection of electronic components, or surgery. Physicians/surgeons who operate within a patient's body require adequate illumination of the field of operation in order to work most effectively. Numerous methods are being used to provide illumination of the field of operation.
For example, overhead lights equipped with parabolic mirrors and polarizing lenses are being used as a general source of non-glare lighting. However, such overhead lights must often be redirected during dental, medical or other procedures to keep the light directed at the point of interest, and the need to readjust the overhead light creates a distraction and requires additional time. Moreover, when the mechanic, hobbyist, surgeon, or physician must lean over the patient or work area to closely observe the field of operation, the overhead light is blocked. In addition, the light source is so far removed from the work location that it is often not possible to direct the overhead light source deep into the area, such as within the patient's body.
It is also known to support a light source from a headband worn by a physician to illuminate an area being viewed by the physician. For example, within U.S. Pat. No. 4,616,257 to Kloots et al., a medical headlight apparatus is disclosed wherein a fiber optic cable transmits light to a headband worn by the physician. The headband supports a housing including an illuminating lens for directing light transmitted by the fiber optic cable toward the field being viewed by the physician. While being an improvement over the above-described overhead light source, the medical headlight apparatus disclosed by Kloots et al. still does not permit the physician or other user to position the light source closely proximate the patient's mouth or other field of operation, and accordingly, the user's hands may block the light from reaching the desired region within the field of operation.
To overcome these problems, a finger-mounted light, such as the one described in U.S. Pat. No. 5,086,378, may be used for illuminating the area. In that invention, for use by a pilot, a fiber optic finger light includes green and red light-omitting diodes (LED) mounted in a housing adapted for strapping to one hand and operated by a 3-position switch. A lens is mounted forwardly of each of the light-emitting diodes and serves to selectively focus light from the light-emitting diodes on one end of one of a pair of light-transmitting fibers which extend through the housing and project from the housing in a flexible duplex fiber optic cable. The light housing is strapped to the wrist and the fiber optic duplex cable is strapped to a finger, such that red or green light emitted from the LED at the opposite end of the optic fiber by manipulation of the switch, may be focused on charts, instruments check lists and the like, in the aircraft.
However, the problem with this approach is the use of an on-off switch for illuminating the area. Clearly, such devices are aimed at being portable devices, and the need to conserve the battery power is extremely important (especially for critical care situations in medical facilities where it is undesirable to have the battery going dead during surgery).